Boost 1.64 introduced a regression where boost::optional deserialisation could lead to a crash when loading the recent chats. This fix updates the way we serialise the ChatListWindow::Chat and HighlightAction classes to avoid these errors. A flag has been added, to allow the use of the erroneous version of the library during the build. During runtime if needed, the client will skip loading the data, to avoid any unpredicted behaviour. Test-Information: Tested on windows 10 with different versions of boost 1.56(bundled), 1.63, 1.64, 1.65 and Ubuntu 17.04 with versions 1.56(bundled) and 1.64. Added unit tests for the serialisation ChatListWindow::Chat class. Change-Id: Idc5c3a6cfd92272b8eab2d77e243dda743803a31